US Army Harbor Defense in WW II:

US Army Harbor Defense in WW II:

An interesting piece on the Mine Groupement, Harbor Defenses of San Francisco, before and during WW II; it gives a good idea of what the Army side of harbor defense would entail in a major defense zone...

Particularly interesting is the obvious level of attention to multiple and concentric rings of defenses - the map is epsecially interesting.

Worth pointing out, of course, is that this article focuses on the Army mine command; naval minefields, Army coast artillery (beyond minefield defense), Army and Navy aviation, naval surface patrols, Harbor Entrance Control Posts, Army installation security missions and methods, and Navy/Coast Guard port security operations are not discussed.

You can put it politely or not, my point was simply that it should be considered a truism that EVERY military establishment is unhappy with the present state of affairs for whatever is being discussed and needs an urgent increase in budget in order to address said state. It's extremely rare to find a counter example where a military establishment says that things are so good that a decrease in budget should be implemented.

Less rare is where some function is considered to be redundant, obsolescent, ill-considered (i.e., not popular) and that the monies involved for it should be transferred to more urgent (i.e., popular) projects. Relevant to another board, you could easily make the case that the battleship deactivations of the early 1990s fall into this latter category.

The attitude that might be inferred (though I don't assume this particular statement is completely serious) is also a truism. Any time one service's capabilities can be thought of as competitive or overlapping with another's, it's just about certain that each service will have an ingrained attitude disparaging and minmizing the 'competing' capabilties of the other service.

The strategic shift for the US after WWII did render US (Army) coast defences redundant, strategically, not technologically or categorically, which is a common erroneous statement. In a given geostrategic situation, there was no inherent absolute superiority of naval over coast defence capablities. Both could have their place, even after WWII.

As of the eve of WWII the US CD's insofar as artillery, were generally obsolescent. There was much investment in the period of 1890's-1900's, some but less around WWI, and relatively little between the wars (although there were a few fully modern batteries built in the 1930's, including at San Fransisco). And the controlled mines discussed in the link were preferable to Navy fields of obsolescent WWI moored mines for defensive purposes near (and the only way to mine right across) heavily travelled channels. Some moored mines always break loose and then present a hazard if contact fuzed, some ships always stumble into defensive minefields through navigational errors and the more so the closer they are placed to a channel. The link doesn't specifically mention the Army WWII era controlled ground mines which were quite formidable, with very large explosive charges.

Once I visited the incomplete army base on the top of the Marin headlands across the Golden Gate from San Francisco. There are to emplacements there for two single 16inch/45 guns plus some tunnels and spotting emplacements. The base was never completed and was never comissioned as an army base but it is very interesting to see. The two guns could have fired on any ship approaching the Golden Gate. The construction was stopped in late 1942 when the IJN had been placed into a defensive position.

It is also worth pointing out that at the time the mine defenses detailed in the post as part of the Harbor Defenses of San Francisco were operational, the fixed coast artillery SEPARATE from the Mine Groupement (ie, the 6 inch and 90 mm guns detailed above) included:

2 16 inch guns
7 12 inch guns
6 12 inch mortars
3 10 inch guns

Source is "Fortress America" (ISBN 0-306-81294-0)

This list would not include DP AA guns or mobile coast and field artillery, ranging up to and potentially including 240 mm pieces.

The battery in Marin might be Battery Townsley, which was completed in 1940. The ordnance was removed from US CD's post WWII with a small handful of exceptions, none 16". As of WWII the defences of SF had 4*16" guns in two batteries. Two other planned 16" batteries in the SF defences were never completed.

US 16" batteries:
4 batteries with the Army's M1919, 16"/50, built in the 20's. 1 each Pearl Harbor, NY (Ft. Tilden in Queens) and Boston consisting of two guns in single open barbette mounts (some later casemated over), and one M1919 on disappearing carriage, Long Island Sound (Great Gull Isl).

2*2-gun using the M1920 16" howitzer, both at Ft. Story VA, early 20's, again open single barbette mounts.

Later in the 20's 3 open barbette 2-gun batteries using ex-USN 16"/45 guns, one Pearl, 2 Panama. Again some later casemated.

Then in late 30's the prototype for war time 16" batteries was built, 2 Navy type 16"/45 in single gun concrete casemates with magazine in the middle, all covered over with earth (and additional 'burster course' of concrete in those early ones): Battery Richmond P. Davis, then Townsley both under HD's of SF.

39 other similar batteries were planned (to the point of numbering them in a 100 series) but only 15 more were completed, mostly well into WWII. Generally in the places listed in the post above. The one I've visited most is on the Navesink Highlands south of Sandy Hook NJ, Battery 116 aka Isaac N. Lewis, completed in 1944, only Navy gun type 16" battery completed in HD's of Southern NY/ HD's of Long Island Sound.

Source is "American Seacoast Defences: A Reference Guide" by Mark A. Berhow, the appendices include an exhaustive list of "modern" (ie. post 1890) batteries. For this and other Coast Defence Studies Group publications and info (focusing mainly on US CD's, but not exclusively):www.cdsg.org/